The component you're referring to, TCA9517DGKR, is part of the Texas Instruments family of ICs. Below, I will explain its pin function specifications, circuit principles, and provide a detailed explanation of the pinout for this specific part.
1. Overview of TCA9517DGKR
The TCA9517DGKR is a Dual Bidirectional I2C Bus Buffer designed to support two I2C bus systems. It is typically used to extend the distance of I2C communication, enabling the connection of I2C devices on different voltage domains and providing signal boosting. The device features low power consumption, level shifting, and bi-directional communication. It's commonly used in applications involving communication between devices that operate at different logic levels.
2. Packaging Information
The TCA9517DGKR comes in a 16-pin TSSOP (Thin Shrink Small Outline Package). This means it has 16 leads, and the "KR" denotes the package type and lead finish.
3. Pin Function Specifications and Detailed Pinout
Here’s a detailed description of each of the 16 pins of the TCA9517DGKR:
Pin Number Pin Name Pin Function 1 VSS Ground pin (GND). This pin is connected to the system ground of the circuit. 2 SCL2 Serial Clock (SCL) line for the second I2C bus (side B). Used for transmitting clock signals. 3 SDA2 Serial Data (SDA) line for the second I2C bus (side B). Used for transmitting data. 4 VCC Supply voltage pin. This pin is connected to the power supply, typically 2.5V to 5.5V. 5 SCL1 Serial Clock (SCL) line for the first I2C bus (side A). Used for transmitting clock signals. 6 SDA1 Serial Data (SDA) line for the first I2C bus (side A). Used for transmitting data. 7 NC No Connect (NC). This pin is not internally connected to the device. 8 NC No Connect (NC). This pin is not internally connected to the device. 9 VSS Ground pin (GND). Connected to the system ground. 10 SCL2 Serial Clock (SCL) line for the second I2C bus (side B). 11 SDA2 Serial Data (SDA) line for the second I2C bus (side B). 12 NC No Connect (NC). This pin is not internally connected to the device. 13 NC No Connect (NC). This pin is not internally connected to the device. 14 SCL1 Serial Clock (SCL) line for the first I2C bus (side A). 15 SDA1 Serial Data (SDA) line for the first I2C bus (side A). 16 VCC Supply voltage pin. Connect to the power supply, typically 2.5V to 5.5V.4. Circuit Principle Description
The TCA9517DGKR acts as a bidirectional buffer for I2C buses. It allows two separate I2C buses to communicate with each other while maintaining the correct voltage levels and timing for each side. The device operates by:
Level shifting: Converts signals from one voltage level to another. For instance, if one I2C bus operates at 5V and the other at 3.3V, the TCA9517DGKR ensures proper communication between these buses. Bidirectional communication: Both the clock (SCL) and data (SDA) lines are bidirectional. This allows devices on both buses to send and receive information. Buffering: It amplifies the signal strength to maintain data integrity over longer distances or multiple connected devices.5. 20 Common FAQ for TCA9517DGKR
Here’s a list of frequently asked questions for the TCA9517DGKR, and their detailed answers:
1. What is the function of the TCA9517DGKR? The TCA9517DGKR is a bidirectional buffer for I2C communication. It extends I2C communication to different voltage domains and helps drive longer bus distances by buffering signals between devices. 2. What is the voltage range of the TCA9517DGKR? The TCA9517DGKR supports a voltage range of 2.5V to 5.5V for both the VCC and I2C buses. 3. How many I2C buses can the TCA9517DGKR handle? The TCA9517DGKR supports two I2C buses: one on side A and another on side B. 4. What is the purpose of the NC pins on the TCA9517DGKR? The NC (No Connect) pins are not internally connected to any part of the IC. They are typically reserved for mechanical or packaging reasons. 5. Can the TCA9517DGKR be used for 1-Wire communication? No, the TCA9517DGKR is designed specifically for I2C communication. It cannot be used for 1-Wire protocol. 6. What is the maximum clock speed supported by the TCA9517DGKR? The TCA9517DGKR supports I2C clock speeds up to 1 MHz (Fast Mode Plus). 7. What happens if the voltage on the SDA and SCL pins is too high? If the voltage on the SDA and SCL pins exceeds the device’s maximum operating voltage (5.5V), the TCA9517DGKR may be damaged. Always ensure the voltage does not exceed the rated limits. 8. How does the TCA9517DGKR handle different voltage domains? The TCA9517DGKR uses level shifting to ensure that the devices on different voltage domains can communicate correctly. 9. Is the TCA9517DGKR compatible with 3.3V logic systems? Yes, the TCA9517DGKR is fully compatible with 3.3V logic systems and can interface with both 3.3V and 5V systems. 10. Can the TCA9517DGKR be used with multiple I2C slaves? Yes, the TCA9517DGKR can buffer communication for multiple I2C slave devices on both buses. 11. What is the power consumption of the TCA9517DGKR? The TCA9517DGKR has a low quiescent current and typical power consumption around 30 µA in standby mode. 12. What are the thermal limitations for the TCA9517DGKR? The TCA9517DGKR is rated for an operating temperature range of -40°C to +125°C. 13. How do I connect the TCA9517DGKR to an I2C system? Connect the SCL and SDA lines from your master/slave I2C devices to the corresponding pins on the TCA9517DGKR. Ensure that the VCC and VSS are connected to the appropriate power and ground rails. 14. **What is the significance of the *VCC* pin?** The VCC pin provides the supply voltage for the device, which can range from 2.5V to 5.5V, and it powers the I2C bus communication. 15. **What is the *SDA* line used for?** The SDA line is the data line in I2C communication, used to transmit and receive data between devices. 16. Does the TCA9517DGKR support I2C arbitration? Yes, it supports I2C arbitration, which allows multiple masters to communicate without conflicts. 17. What are the main benefits of using the TCA9517DGKR? The main benefits include extended communication range, voltage level shifting, and support for bidirectional communication across different I2C buses. 18. Can I use the TCA9517DGKR for high-speed I2C applications? While the TCA9517DGKR supports clock speeds up to 1 MHz, it is not recommended for high-speed I2C applications beyond that rate. 19. Can I chain multiple TCA9517DGKRs together? Yes, you can cascade multiple TCA9517DGKR buffers if you need to extend the I2C communication even further. 20. How do I ensure proper grounding for the TCA9517DGKR? Ensure that the VSS pin is properly connected to the ground of your circuit to avoid communication issues.Conclusion
The TCA9517DGKR is an excellent choice for applications requiring I2C communication between different voltage domains or for extending I2C bus distances. The 16-pin TSSOP package, combined with its ability to shift voltage levels and buffer signals, makes it a powerful solution for managing I2C communications in complex systems.
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